AA amyloidosis secondary to adult onset Still's disease: About 19 cases.

Objective: Adult onset Still's disease (AOSD) is an inflammatory disorder characterized by high spiking fever, evanescent rash, polyarthritis, and many other systemic manifestations. Recurrent or persistent disease can lead to AA amyloidosis (AAA). Our objectives were to present 3 French cases and perform a systematic review of the literature, in order to determine the prevalence, characteristics, predisposing factors, and therapeutic response of AOSD-related AAA.

Methods: A systematic literature review was performed by searching MEDLINE from 1971 to 2018. Two independent investigators selected reports of AAA complicating AOSD. New French cases were identified with the help of the Reference Center for rare Auto-Inflammatory Diseases and Amyloidosis (CEREMAIA). Patients with juvenile idiopathic arthritis were excluded.

Results: The prevalence of AAA in AOSD was 0.88% (95%CI [0.49-1.28]) based on 45 articles. In addition to 3 new cases from the CEREMAIA, 16 patients were assessed for clinical presentation, risk factors, and therapeutic response of AOSD-related AAA. Mean age at AOSD onset was 29.6 ± 12.6 years, with a mean delay before AAA diagnosis of 16.75±5.8 years. Renal involvement was the most common manifestation of AAA. The majority of patients presented active AOSD at AAA diagnosis. Various treatments of AOSD-related AAA were attempted including corticosteroids and biotherapies.

Conclusion: AAA is a rare and severe complication that may occur during the course of uncontrolled active AOSD. It could be prevented by early diagnosis and better control of AOSD, with more frequent use of biotherapies.